1. Field
The present disclosure relates generally to aircraft and, in particular, to fuel use in an aircraft. Still more particularly, the present disclosure relates to a method and apparatus for predicting fuel for an aircraft.
2. Background
In operating an aircraft, an operator, such as a pilot or a dispatcher, creates a flight plan, monitors the use of fuel for a flight of an aircraft, or both creates a flight plan and monitors fuel use. For example, when creating a flight plan, the operator, such as a dispatcher, identifies the amount of fuel needed for the flight. The amount of fuel needed by an aircraft also takes into account different rules and regulations that specify how much fuel should be available for different situations in addition to the fuel needed to reach the destination.
For example, the operator may identify the amount of fuel needed to reach the destination, the fuel needed if placed in a holding pattern, the fuel needed if the aircraft is sent to an alternate destination in the flight plan, and captain's fuel as the reserve. The identifications are for types of fuel use for the aircraft.
The amount of fuel planned for use by an aircraft may be adjusted or selected by the pilot prior to takeoff. For example, when the aircraft is at the gate and being refueled, the pilot may review the flight plan and make changes to the amount of fuel for the aircraft based on various factors. These factors may include weather conditions, efficiency of the current aircraft, reaching the destination at a particular time, and other suitable factors.
The fuel present in the aircraft is indicated through a display system. The display system displays the amount of fuel present in the fuel tanks. This display currently shows the amount of fuel with units in the form of the weight of the fuel. If the pilot is uncomfortable with the amount of fuel present or planned for the flight, the pilot may order additional fuel to be placed into the fuel tanks.
To determine whether additional fuel may be needed, the operator performs calculations as to whether the fuel present or planned is sufficient to reach the destination and meet other rules and regulations regarding the amount of fuel that should be present for the flight to cover different contingencies. These types of calculations are time-consuming and involve concentration by the operator.
For example, these types of operations may be performed in the aircraft by a pilot prior to flight in addition to other operations for preflight checks and planning. With the number of different operations to perform prior to take off, the pilot may err on the side of caution and add more fuel than may be needed to meet a desired safety factor.
Additional fuel increases the weight of the aircraft. As the weight of the aircraft increases, the fuel consumption of the aircraft increases. As a result, the increased fuel use may increase the cost of the flight more than desired. Therefore, it would be desirable to have a method and apparatus that take into account at least some of the issues discussed above, as well as other possible issues.